1. Field of the Invention
The present invention relates generally to an air conditioner for use in an automotive vehicle, and more particularly, to an air conditioner capable of appropriately adjusting the amount of air to be introduced into the interior of an automotive vehicle at the time of starting the air conditioner so that the comfortability may be improved.
2. Description of the Related Art
When an air conditioner of an automotive vehicle parked outdoors in hot weather is started, a great amount of air is emitted from the air conditioner to a passenger compartment in order to rapidly lower the temperature of this compartment. However, it is impossible to cool the air immediately after the air conditioner starts operating because the temperature of cooling components, for example an evaporator and the like, is high. Therefore, a great amount of hot air is emitted into the passenger compartment, thus lowering the comfortability.
An air conditioner as disclosed in Japanese Utility Model Laid-open Application (unexamined) No. 61 -142616 comprises a temperature detecting means for detecting the surface temperature of a heat exchanger mounted therein and a time measuring means for measuring the lapse of time after the air conditioner has been switched on. According to this disclosure, a relatively small amount of air is supplied to a passenger compartment when the temperature detected by the temperature detecting means is greater than a predetermined temperature and the period of time measured by the time measuring means is less than a predetermined period of time, thus preventing a great amount of hot air from being introduced into the passenger compartment at the time of starting the air conditioner.
Conventionally, even when an air conditioner is switched on in spring or autumn in which everybody does not feel so hot, a great amount of air is emitted into a passenger compartment in order to rapidly minimize the difference between the actual temperature of the passenger compartment and the setting temperature. Thus, there arises the problem that the comfortability is lowered.
In order to solve this kind of problem, when the temperature of the passenger compartment or the amount of solar radiation exceeds a predetermined value, the above-described control is performed to restrict the amount of air to a relatively small amount at the time of starting the air conditioner. It is further considered that when the temperature of the passenger compartment and the amount of solar radiation are less than respective predetermined values, the time required for increasing the amount of air from a predetermined small amount to a predetermined large amount is prolonged.
More specifically, when it is necessary to rapidly cool the passenger compartment because the temperature thereof or the amount of solar radiation exceeds the predetermined value, the amount of air fed from the air conditioner is rapidly increased to a large amount (Hi) after a starting control period T2' by the small amount (Lo) of air has elapsed as shown by a solid line in FIG. 1 or when the temperature of air from the air conditioner has become lower than a predetermined value. On the other hand, when the passenger compartment is gradually cooled because the temperature thereof and the amount of solar radiation are less than respective predetermined values, the amount of air is gradually increased to the amount (Hi), as shown by a dotted line in FIG. 1. Thus, not only a great amount of hot air is prevented from being introduced into the passenger compartment at the time of starting the air conditioner, but the passenger compartment can be rapidly cooled in summer and gradually cooled in spring or autumn.
Generally speaking, since a compressor of a refrigerator of an air conditioner is coupled to an output shaft of an engine, the compressor consumes part of the engine output. Accordingly, the engine output is reduced by the operation of the compressor, thus lowering the starting performance of the engine. It is, therefore, considered that the compressor is kept stopped for a predetermined period of time at the time of engine starting.
However, if the compressor is not operated when the engine starts, the cooling of the evaporator is delayed, which leads to the delay in starting the air cooling operation. As such, even though the amount of air is reduced for the predetermined period of time at the time of starting the air conditioner, it is difficult to effectively remove uncomfortableness of a driver or other passengers due to hot air introduced into the passenger compartment, particularly in summer.